Dewatering of organic suspensions with anionic and cationic polymers

摘要

A process of dewatering an aqueous suspension of suspended organic solids comprising adding to the suspension an aqueous composition comprising a first water-soluble ionic polymeric flocculant and a second water-soluble ionic polymeric flocculant in which the first flocculant is in excess over the second flocculant and the first and second flocculants are counterionic and in the aqueous composition at least a portion of the first flocculant and at least a portion of the second flocculant form particles of counterionic precipitate. Characterised in that the particles of counterionic precipitate are of size at least 90 wt.% above 100 mm in the aqueous composition and substantially all of the portion of the first flocculant which is not contained in the particles of counterionic precipitate is in solution.